The Chesapeake Bay Watershed, the largest estuary in North America, covers 64,000 square miles and includes more than 150 rivers and streams that drain into the bay. Roughly one quarter of the land in the watershed is used for agricultural production, and agricultural practices can affect the health of those rivers and streams, and ultimately the bay itself.
While the health of the Chesapeake Bay has improved since the 1970s, excess nutrients and sediment continue to adversely affect water quality in local rivers and streams, which contributes to impaired water quality in the bay.